R is a language and environment for statistical computing and graphics.
It is a GNU project which is similar to the S language and environment
which was developed at Bell Laboratories (formerly AT&T, now Lucent
Technologies) by John Chambers and colleagues. R can be considered as a
different implementation of S. There are some important differences, but
much code written for S runs unaltered under R.

R provides a wide variety of statistical (linear and nonlinear
modelling, classical statistical tests, time-series analysis,
classification, clustering, ...) and graphical techniques, and is highly
extensible.
